Question 1

Which of the following would be an appropriate null hypothesis?

Accepted Answer

A) The population proportion is equal to 0.60. 
B) The sample proportion is equal to 0.60. 
C) The population proportion is not equal to 0.60. 
D) All of these choices are true. 
A) The population proportion is equal to 0.60. 
B) The sample proportion is equal to 0.60. 
C) The population proportion is not equal to 0.60. 
D) All of these choices are true. A

Question 2

The sample mean   is a consistent estimator of the population mean m .

Accepted Answer

A) True 
 B)False  True

Question 3

In selecting the sample size to estimate the population proportion p , if we have no knowledge of even the approximate values of the sample proportion   , we:

Accepted Answer

A) take another sample and estimate   . 
B) take two more samples and find the average of their   . 
C) let   = 0.50. 
D) let   = 0.95. 
A) take another sample and estimate   . 
B) take two more samples and find the average of their   . 
C) let   = 0.50. 
D) let   = 0.95. C

Question 4

Which of the following is not a characteristic for a good estimator?

Accepted Answer

A) Being unbiased 
B) Being consistent 
C) Having relative efficiency 
D) All of these choices are true. 
A) Being unbiased 
B) Being consistent 
C) Having relative efficiency 
D) All of these choices are true.

Question 5

Which of the following statements is true?

Accepted Answer

A) The sample mean is relatively more efficient than the sample median. 
B) The version of the sample variance where you divide by n is biased. 
C) The sample mean is consistent. 
D) All of these choices are true. 
A) The sample mean is relatively more efficient than the sample median. 
B) The version of the sample variance where you divide by n is biased. 
C) The sample mean is consistent. 
D) All of these choices are true.

Question 6

An unbiased estimator is said to be consistent if the difference between the estimator and the parameter grows smaller as the sample size grows larger.

Accepted Answer

A) True 
 B)False

Question 7

A point estimator is defined as:

Accepted Answer

A) a range of values that estimates an unknown population parameter. 
B) a single value that estimates an unknown population parameter. 
C) a range of values that estimates an unknown sample statistic. 
D) a single value that estimates an unknown sample statistic. 
A) a range of values that estimates an unknown population parameter. 
B) a single value that estimates an unknown population parameter. 
C) a range of values that estimates an unknown sample statistic. 
D) a single value that estimates an unknown sample statistic.

Question 8

In determining the sample size needed to estimate the population proportion p, we let the sample proportion   = 1 if we have no knowledge of even the approximate values of   .

Accepted Answer

A) True 
 B)False

Question 9

An interval estimate is a range of values within which the actual value of the population parameter, such as m , may fall.

Accepted Answer

A) True 
 B)False

Question 10

An unbiased estimator has an average value (across all samples)equal to the population parameter.

Accepted Answer

A) True 
 B)False

Question 11

The 95% confidence interval would indicate that, for this shipment, the proportion of defective fuses is between 0 and 0.28.

Accepted Answer

A) True 
 B)False

Question 12

The formula   is used to find the sample size needed to estimate a population proportion. In this formula, B represents the ____________________ on the error of estimation.

Accepted Answer

The answer of The formula   is used to...

Question 13

If there are two unbiased estimators of a population parameter available, the one that has the smallest variance is said to be:

Accepted Answer

A) a biased estimator. 
B) relatively efficient. 
C) consistent. 
D) relatively unbiased. 
A) a biased estimator. 
B) relatively efficient. 
C) consistent. 
D) relatively unbiased.

Question 14

When determining the required sample size for a confidence interval, you need to know the population ____________________, the confidence ____________________, and the ____________________ on the error of estimation.

Accepted Answer

standard d

Question 15

The width of a confidence interval estimate for a proportion will be:

Accepted Answer

A) narrower for 90% confidence than for 95% confidence. 
B) wider for a sample size of 100 than for a sample size of 50. 
C) narrower for 99% confidence than for 95% confidence. 
D) narrower when the sample proportion if 0.50 than when the sample proportion is 0.20. 
A) narrower for 90% confidence than for 95% confidence. 
B) wider for a sample size of 100 than for a sample size of 50. 
C) narrower for 99% confidence than for 95% confidence. 
D) narrower when the sample proportion if 0.50 than when the sample proportion is 0.20.

Question 16

The sampling distribution of   is approximately normal if the sample size is more than 30.

Accepted Answer

A) True 
 B)False

Question 17

Assuming that all necessary conditions are met, what needs to be changed in the formula   so that we can use it to construct a (1 - a )confidence interval estimate for the population proportion p ?

Accepted Answer

A)    should be replaced by p . 
B) t a  should be replaced by z a  . 
C) t a  should be replaced by t  a \ 2. 
D) t a  should be replaced by z  a \ 2. 
A)    should be replaced by p . 
B) t a  should be replaced by z a  . 
C) t a  should be replaced by t  a \ 2. 
D) t a  should be replaced by z  a \ 2.

Question 18

Explain briefly why interval estimators are preferred to point estimators.

Accepted Answer

An interval estimator incorpor

Question 19

An unbiased estimator of a population parameter is defined as:

Accepted Answer

A) an estimator whose expected value is equal to the parameter. 
B) an estimator whose variance is equal to one. 
C) an estimator whose expected value is equal to zero. 
D) an estimator whose variance goes to zero as the sample size goes to infinity. 
A) an estimator whose expected value is equal to the parameter. 
B) an estimator whose variance is equal to one. 
C) an estimator whose expected value is equal to zero. 
D) an estimator whose variance goes to zero as the sample size goes to infinity.

Question 20

A specific confidence interval obtained from data will always correctly estimate the population parameter.

Accepted Answer

A) True 
 B)False

Which of the following would be an appropriate null hypothesis?

The sample mean is a consistent estimator of the population mean m .

In selecting the sample size to estimate the population proportion p , if we have no knowledge of even the approximate values of the sample proportion , we:

Which of the following is not a characteristic for a good estimator?

Which of the following statements is true?

An unbiased estimator is said to be consistent if the difference between the estimator and the parameter grows smaller as the sample size grows larger.

A point estimator is defined as:

In determining the sample size needed to estimate the population proportion p, we let the sample proportion = 1 if we have no knowledge of even the approximate values of .

An interval estimate is a range of values within which the actual value of the population parameter, such as m , may fall.

An unbiased estimator has an average value (across all samples)equal to the population parameter.

The 95% confidence interval would indicate that, for this shipment, the proportion of defective fuses is between 0 and 0.28.

The formula is used to find the sample size needed to estimate a population proportion. In this formula, B represents the ____________________ on the error of estimation.

If there are two unbiased estimators of a population parameter available, the one that has the smallest variance is said to be:

When determining the required sample size for a confidence interval, you need to know the population , the confidence , and the on the error of estimation.

The width of a confidence interval estimate for a proportion will be:

The sampling distribution of is approximately normal if the sample size is more than 30.

Assuming that all necessary conditions are met, what needs to be changed in the formula so that we can use it to construct a (1 - a )confidence interval estimate for the population proportion p ?

Explain briefly why interval estimators are preferred to point estimators.

An unbiased estimator of a population parameter is defined as:

A specific confidence interval obtained from data will always correctly estimate the population parameter.

What Is Statistics

Graphical and Tabular Descriptive Techniques

Numerical Descriptive Techniques

Data Collection and Sampling

Probability

Random Variables and Discrete Probability Distributions

Continuous Probability Distributions

Sampling Distributions

Introduction to Hypothesis Testing

Inference About a Population

Inference About Comparing Two Populat

Inference About Comparing Two Populat

Analysis of Variance

Chi-Squared Tests

Simple Linear Regression and Correlat

Multiple Regression

Review of Statistical Inference

Filters

Exam 9: Introduction to Estimation

Which of the following would be an appropriate null hypothesis?

The sample mean is a consistent estimator of the population mean m .

In selecting the sample size to estimate the population proportion p , if we have no knowledge of even the approximate values of the sample proportion , we:

Which of the following is not a characteristic for a good estimator?

Which of the following statements is true?

An unbiased estimator is said to be consistent if the difference between the estimator and the parameter grows smaller as the sample size grows larger.

A point estimator is defined as:

In determining the sample size needed to estimate the population proportion p, we let the sample proportion = 1 if we have no knowledge of even the approximate values of .

An interval estimate is a range of values within which the actual value of the population parameter, such as m , may fall.

An unbiased estimator has an average value (across all samples)equal to the population parameter.

The 95% confidence interval would indicate that, for this shipment, the proportion of defective fuses is between 0 and 0.28.

The formula is used to find the sample size needed to estimate a population proportion. In this formula, B represents the ____________________ on the error of estimation.

If there are two unbiased estimators of a population parameter available, the one that has the smallest variance is said to be:

When determining the required sample size for a confidence interval, you need to know the population ____________________, the confidence ____________________, and the ____________________ on the error of estimation.

The width of a confidence interval estimate for a proportion will be:

The sampling distribution of is approximately normal if the sample size is more than 30.

Assuming that all necessary conditions are met, what needs to be changed in the formula so that we can use it to construct a (1 - a )confidence interval estimate for the population proportion p ?

Explain briefly why interval estimators are preferred to point estimators.

An unbiased estimator of a population parameter is defined as:

A specific confidence interval obtained from data will always correctly estimate the population parameter.

What Is Statistics

Graphical and Tabular Descriptive Techniques

Numerical Descriptive Techniques

Data Collection and Sampling

Probability

Random Variables and Discrete Probability Distributions

Continuous Probability Distributions

Sampling Distributions

Introduction to Hypothesis Testing

Inference About a Population

Inference About Comparing Two Populat

Inference About Comparing Two Populat

Analysis of Variance

Chi-Squared Tests

Simple Linear Regression and Correlat

Multiple Regression

Review of Statistical Inference

Filters

When determining the required sample size for a confidence interval, you need to know the population , the confidence , and the on the error of estimation.